The present invention refers to protective mask. The traditional protective masks, usually called "gas masks", comprise essentially a rubber face-shield, associated to means to fit it to the user's head. This face-shield carries the devices necessary to the breathing, to the feeding and some other ones, together with an ocular surface, which can be realized by one or two separate elements.
Therefore the face-shields are structured in such a way that they are strong enough to withstand the stresses due to the weight of the transparent surface and of the remaining devices necessary to the operation of the mask. At the same time they have a deformable edge, able to follow the configuration of the face, assuring the required tightness without prejudice to the comfortable use of the mask.
Therefore the current masks are realized trying to mediate the opposite requirements of stiffness and of tightness and comfort, which are obviously in contrast. Moreover the transparent surfaces of said masks are often of reduced extension limiting the width of the field of view; whenever they are wide, they show a concave development which compromises the use of optical devices as for instance binoculars or similar.